5,946 research outputs found
The Very Basics of Sustainability - an Alternative Viewpoint
This paper examines the context and meaning of the term ‘sustainability’, the factors that determine and govern climate on Earth, the population of the Earth and its trends and influencers, the requirements for sustaining life and the options that are available to humankind. Some viewpoints are presented that are alternative to ‘conventional alternative’ thinking. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’ and also argues that humankind needs to face up to the population size that the Earth can sustain and the desired sustainable distribution of wealth
Index to 1981 NASA Tech Briefs, volume 6, numbers 1-4
Short announcements of new technology derived from the R&D activities of NASA are presented. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This index for 1981 Tech Briefs contains abstracts and four indexes: subject, personal author, originating center, and Tech Brief Number. The following areas are covered: electronic components and circuits, electronic systems, physical sciences, materials, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences
A program of X-ray astronomy from sounding rocket Final report
X-ray astronomy from sounding rocket
A mathematical model of a large open fire
A mathematical model capable of predicting the detailed characteristics of large, liquid fuel, axisymmetric, pool fires is described. The predicted characteristics include spatial distributions of flame gas velocity, soot concentration and chemical specie concentrations including carbon monoxide, carbon dioxide, water, unreacted oxygen, unreacted fuel and nitrogen. Comparisons of the predictions with experimental values are also given
Optimization of canopy conductance models from concurrent measurements of sap flow and stem water potential on Drooping Sheoak in South Australia
This project is supported by National Centre for Groundwater Research and Training (NCGRT, Australia). The first author is supported by China Scholarship Council and NCGRT for his PhD study at Flinders University of South Australia. Xiang Xu and Yunhui Guo provided assistance in the field. Constructive comments and suggestion from three anonymous reviewers significantly improve the manuscript. This article also appears in: Patterns in Soil-Vegetation-Atmosphere Systems: Monitoring, Modelling and Data Assimilation.Peer reviewedPublisher PD
Using Sacred Notions Of Time And Space To Map The Hidden Stories Of The Finch Hydro Corridor
The components of my MES portfolio largely draw on research that I have done over the past year in the MES program. The intention of the portfolio is to use different popular education and arts based methods to communicate this research to different audiences including members of the Jane-Finch community. The components of my final portfolio include: a walking tour, a series of postcards, a discussion of the takeover of the campus and community radio station CHRY 105.5FM, and two workshop presentations on the research I have done on the fossil fuel industry through the OPIRG-York working group Environmental Justice @ York. These different components use popular education and community arts methods to share the hidden and erased stories in the Finch Hydro Corridor. The components utilize a combination of visual, tactile and auditory tools to engage the different senses in the storytelling process. The components tell the same stories in different ways to engage different audiences and build greater awareness of the issues. Each of the components of my portfolio contributes to accomplishing different learning objectives in my plan of study that focus on the work of decolonization, environmental justice, popular education, and community arts
The measurement of solar spectral irradiances at wavelengths between 40 and 4000 A
Two 1/8-meter Ebert-Fastie spectrometers were refurbished and upgraded in order to measure the solar spectral irradiances between 1160 A and 3100 A. An evacuated 1/4-meter normal-incidence spectrometer was also fabricated for spectral irradiance measurements over the wavelength range from 1250 A to 250 A. Procedures were developed for the calibration of all three instruments utilizing standards at the National Bureau of Standards. The two 1/8-meter spectrometers were flown to measure the solar spectral irradiances near solar maximum on two different dates. Data from these flights were analyzed. The performance of the spectrometers, and the results of an analysis of the variabilities of the solar spectral irradiances over the solar cycles 20 and 21 are discussed
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Patterns of CO2 and radiocarbon across high northern latitudes during International Polar Year 2008
High-resolution in situ CO2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007-2008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub-Arctic to the North Pole from 0.04 to 12 km altitude in spring and summer of 2008. Influences on the observed CO2 concentrations were investigated using coincident CO, black carbon, CH3CN, HCN, O3, C2Cl4, and Δ14CO2 data, and the FLEXPART model. In spring, the CO2 spatial distribution from 55̊N to 90̊N was largely determined by the long-range transport of air masses laden with Asian anthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv-1 with the highest anthropogenic content registered in plumes sampled poleward of 80̊N. In summer, the CO2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of northern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO2 to CO emission ratios of 4 to 16 ppmv ppmv-1 and a mean CO2 emission factor of 1698 ± 280 g kg-1 dry matter. From the 14C in CO2 content of 48 whole air samples, mean spring (46.6 ± 4.4%) and summer (51.5 ± 5%) D14CO2 values indicate a 5%seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted Δ14CO2 values were observed in <1% of the data set. Rather, ARCTAS Δ14CO2 observations (54%) revealed predominately a pattern of positive disequilibrium (1-7%) with respect to background regardless of season owing to both heterotrophic respiration and fire-induced combustion of biomass. Anomalously enriched Δ14CO2 values (101-262%) measured in emissions from Lake Athabasca and Eurasian fires speak to biomass burning as an increasingly important contributor to the mass excess in Δ14CO2 observations in a warming Arctic, representing an additional source of uncertainty in the quantification of fossil fuel CO2
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